I think there is a very important distinction that needs to be made. The popular reddit experience is vastly worse than the customized reddit. It took me a while to realize that my reddit experience was vastly improved once I was very picky about which subreddits I follow.
It’s not really relevant to what the author is trying to say at all. Actually, it’s the opposite. Because of the excess of disinterested capital that only values growth, a thing that could be a positive and productive thing is instead a cancer — it grows and grows without purpose. That’s why Reddit (and Tumblr) have massive porn sections that aren’t spoken about and Reddit is a watering hole for white supremacy and p…
That's the core of reddit, which was founded as a normie 4chan at the beginning of a time when many sites were trying to monetize the energy coming from that corner of the internet. The parts that you like are an outgrowth of that, and originally essentially subsidized by it. The fact that when you remove that element completely, you don't have a business (there have been many attempts at a "civil" reddit), shows that it still is.
There was already a metafilter. If part of you, at least part of the time, wasn't attracted to the id of reddit, you probably would have been on metafilter.
Tumblr is a different case - just a blogging site with social extensions - and there have always been porn blogs (and nazi blogs, but the social element of tumblr happened to pull it into a different direction.)